安卓几种常用函数

1.保存图片文件到SD卡

	private InputStream Bitmap2IS(Bitmap bm) {
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		bm.compress(Bitmap.CompressFormat.PNG, 100, baos);
		InputStream sbs = new ByteArrayInputStream(baos.toByteArray());
		return sbs;

	}

	public void onClick_SaveImageToSDCard(View view) {
		try {
			FileOutputStream fos = new FileOutputStream(ALBUM_PATH
					+ "/QRcode.png");
			// InputStream is = getResources().getAssets().open("image.jpg");
			InputStream is = Bitmap2IS(bit);
			byte[] buf = new byte[4096];
			int count = 0;
			while ((count = is.read(buf)) >= 0) {
				fos.write(buf, 0, count);
			}
			fos.close();
			is.close();
			/*
			 * byte[] buffer = new byte[8192]; int count = 0; while((count =
			 * is.read(buffer)) >= 0){ fos.write(buffer,0,count); } fos.close();
			 * is.close();
			 */
			Toast.makeText(this, "写入成功！", Toast.LENGTH_LONG).show();
		} catch (Exception e) {
			// TODO: handle exception
			Toast.makeText(this, e.getMessage(), Toast.LENGTH_LONG).show();
		}
	}